A NEW SPECIES OF TREMATODE OF THE FAMILY 

 HETEROPHYIDAE, WITH A NOTE ON THE GENUS 

 APOPHALLUS AND RELATED GENERA 



By Emmett W. Price 



Parasitologist, Zoological Division, Bureau of Animal Industry, United States 

 Department of Agriculture 



During the summer of 1929, Dr. Eloise B. Cram, of the Zoological 

 Division, Bureau of Animal Industry, conducted an investigation in 

 cooperation with representatives of the Bureau of Biological Survey 

 to determine if parasites were a factor in causing the death of ducks 

 from the so-called " duck disease " at Klamath Falls, Oreg. Among 

 the specimens of parasites collected from water birds in this 

 vicinity were a number of trematodes, one species of which appears 

 to be new. This fluke belongs to the family Heterophyidae Odhner, 

 1914, and to the genus Apophallus Liihe, 1909. For this trematode 

 the name A'pophallus crami is proposed, the species being named for 

 the collector. 



APOPHALLUS CRAMI, new species 

 FiGXJEE 1 



Specific diagnosis. — Apophallus : Bod}^ slender, 1.5 mm. to 1.9 mm. 

 long by 279/i. to 341(U, wide in the vicinity of the testes; preacetabular 

 portion of bod}^ flattened and showing a slight constriction in the 

 region between the acetabulum and the intestinal bifurcation ; postace- 

 tabular portion more or less cylindrical. The cuticle is covered with 

 small scalelike spines. Oral sucker subterminal, 45/i, to GO/x in diame- 

 ter; prepharynx ver}^ short; pharynx ovoid, 45/a long by SO^a witle. 

 Esophagus slender, about 337;u long, bifurcating about one-fifth of 

 the body length from the anterior end ; intestinal ceca slender, extend- 

 ing to near the posterior end of the body. Acetabulum 52//, to 62/a in 

 diameter, situated at the equator of the body and opening into the 

 genital sinus. Genital pore at anterior end of genital sinus, the 

 aperture being guarded by two ovoid, papillalike gonotyls. Testes 

 globular or slightly ovid in shape and placed obliquely in the poste- 



No. 2883.— Proceedings U. S. National Museum. Vol. 79, Art. 17 



59431—31 1 



